{"id":"b607f6c9-0bb6-5213-b539-1416935fe543","stable_key":"548ab9d6-3a9b-5bed-879c-17d03813b636:transport-rfvt3-low-ph","predicate":"transports","statement":"Lowering extracellular pH from 7.5 to 5.5 increased RFVT3-mediated riboflavin uptake and changed its apparent kinetic parameters.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"f8d1e143-68d7-52db-a6cd-e29123128f98","mechanism_event_label":"Acidic conditions enhanced RFVT3 transport in the experiment.","subject":{"id":"036b3828-9ad7-5a41-9e89-119cef5c3665","slug":"slc52a3","display_name":"Riboflavin transporter 3 / SLC52A3","entity_type_key":"protein"},"object":{"id":"86eb1eee-a8d1-539c-8c17-0911f69b6f1b","slug":"riboflavin","display_name":"Riboflavin (vitamin B2)","entity_type_key":"small_molecule"},"evidence_count":1,"mechanism_event":{"id":"f8d1e143-68d7-52db-a6cd-e29123128f98","stable_key":"548ab9d6-3a9b-5bed-879c-17d03813b636:transport-rfvt3-low-ph-event","event_type":"biochemical_relationship","label":"Acidic conditions enhanced RFVT3 transport in the experiment.","description":"Lowering extracellular pH from 7.5 to 5.5 increased RFVT3-mediated riboflavin uptake and changed its apparent kinetic parameters.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"036b3828-9ad7-5a41-9e89-119cef5c3665","slug":"slc52a3","display_name":"Riboflavin transporter 3 / SLC52A3","entity_type_key":"protein"},"role":"transporter","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"86eb1eee-a8d1-539c-8c17-0911f69b6f1b","slug":"riboflavin","display_name":"Riboflavin (vitamin B2)","entity_type_key":"small_molecule"},"role":"substrate","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""}]},"contexts":[{"dimension":"evidence_location","value_text":"Figure 1c-e","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Human RFVT3 expression and stable-isotope uptake","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"pH 5.5 versus 7.5; 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topical membership is not evidence of a direct dietary effect.\nplain_language: Acidic conditions enhanced RFVT3 transport in the experiment.\norganism: Homo sapiens\ntissue_or_cell_type: HEK293T cells\nexperimental_model: Human RFVT3 expression and stable-isotope uptake\nlimitations: In vitro pH comparison; not advice to alter gastrointestinal acidity.\nexposure: pH 5.5 versus 7.5; concentration-dependent [13C]riboflavin uptake.\nevidence_location: Figure 1c-e\n[transport-rfvt-structure-2025] Structure and transport mechanism of human riboflavin transporters (2025). https://pmc.ncbi.nlm.nih.gov/articles/PMC12044054/ DOI: 10.1038/s41467-025-59255-7","model_system":"Human RFVT3 expression and stable-isotope uptake","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [transport-rfvt-structure-2025] Structure and transport mechanism of human riboflavin transporters (2025). https://pmc.ncbi.nlm.nih.gov/articles/PMC12044054/ DOI: 10.1038/s41467-025-59255-7","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"4f7c9578-82bf-5e2d-b5c4-72a79fb4f6af","stable_key":"import-548ab9d6-3a9b-5bed-879c-17d03813b636","title":"Riboflavin: mechanisms, deficiency and nutrient interactions (2026-09-17)","document_type":"imported_text","citation_label":"AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text.","file_path":"","sha256":"680cb6bc8249877f2410f551807f10d390fdd719014137d7414ba3420e29228d","revision_id":"7a61e299-908d-5372-860b-99ed190f9d7a","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}